Re: Last Call: SMTP Service Extension for Content Negotiation to Proposed Standard

[Dave Crocker <dhc2 at dcrocker.net>]

At 07:49 PM 7/2/2002 -0400, John C Klensin wrote:
> --On Tuesday, 02 July, 2002 15:33 -0600 Alexey Melnikov
> <mel at MESSAGINGDIRECT.COM> wrote:
> >  Correct me if
> > I am wrong, but it seams that extending VRFY command is more
> > appropriate for the purpose than using RCPT.
>
> Hmm.  _That_ is an interesting idea, since we have always
> permitted VRFY to do somewhat more poking around in real time
> than one might normally expect of RCPT (where "poking around"
> efforts more often result in a 250 code and an email rejection
> if needed).


If I understand both your comments and Keith's suggestion, the key is a 
separate command.

It, too, find that aesthetically preferable.  The problem is with efficiency.

A separate command means 2 commands per recipient and it means at least one 
synchronization event, between issuance of this new command and issuance of 
the first RCPT-TO.

That's quite a bit of overhead, for something that frequently will have no 
effect on the content being transferred.

d/

----------
Dave Crocker <mailto:dave at tribalwise.com>
TribalWise, Inc. <http://www.tribalwise.com>
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